Ambitious Dragonborn

Ambitious Dragonborn enters with X +1/+1 counters on it, where X is the greatest power among creatures you control and creature cards in your graveyard.

Accomplished Automaton

Fabricate 1 (When this creature enters, put a +1/+1 counter on it or create a 1/1 colorless Servo artifact creature token.)

Boon of Safety

Put a shield counter on target creature. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
Scry 1.

Timberland Guide

When Timberland Guide enters, put a +1/+1 counter on target creature.

Bloom Hulk

When Bloom Hulk enters, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Guardian Gladewalker

Changeling (This card is every creature type.)
When Guardian Gladewalker enters, put a +1/+1 counter on target creature.

Ainok Bond-Kin

Outlast {1}{W} ({1}{W}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has first strike.

Sporeback Troll

Graft 2 (This creature enters with two +1/+1 counters on it. Whenever another creature enters, you may move a +1/+1 counter from this creature onto it.)
{1}{G}: Regenerate target creature with a +1/+1 counter on it.

Hamza, Guardian of Arashin

This spell costs {1} less to cast for each creature you control with a +1/+1 counter on it.
Creature spells you cast cost {1} less to cast for each creature you control with a +1/+1 counter on it.

Annoyed Altisaur

Reach, trample
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Ulamog's Crusher

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents.)
Ulamog's Crusher attacks each combat if able.

Celebrity Fencer

Alliance — Whenever another creature you control enters, put a +1/+1 counter on Celebrity Fencer.

Lifecraft Cavalry

Trample
Revolt — Lifecraft Cavalry enters with two +1/+1 counters on it if a permanent you controlled left the battlefield this turn.

Scrounging Bandar

Scrounging Bandar enters with two +1/+1 counters on it.
At the beginning of your upkeep, you may move any number of +1/+1 counters from Scrounging Bandar onto another target creature.

Clockwork Beetle

Clockwork Beetle enters with two +1/+1 counters on it.
Whenever Clockwork Beetle attacks or blocks, remove a +1/+1 counter from it at end of combat.

Advocate of the Beast

At the beginning of your end step, put a +1/+1 counter on target Beast creature you control.

Eldrazi Devastator

Ivy Lane Denizen

Whenever another green creature you control enters, put a +1/+1 counter on target creature.

Bond Beetle

When Bond Beetle enters, put a +1/+1 counter on target creature.

Greater Sandwurm

Greater Sandwurm can't be blocked by creatures with power 2 or less.
Cycling {2} ({2}, Discard this card: Draw a card.)

Burst of Strength

Put a +1/+1 counter on target creature and untap it.

Thallid

At the beginning of your upkeep, put a spore counter on Thallid.
Remove three spore counters from Thallid: Create a 1/1 green Saproling creature token.

Basri's Acolyte

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
When Basri's Acolyte enters, put a +1/+1 counter on each of up to two other target creatures you control.

Tuskguard Captain

Outlast {G} ({G}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has trample.

Snakeskin Veil

Put a +1/+1 counter on target creature you control. It gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Graypelt Hunter

Trample
Whenever Graypelt Hunter or another Ally you control enters, you may put a +1/+1 counter on Graypelt Hunter.

Aquastrand Spider

Graft 2 (This creature enters with two +1/+1 counters on it. Whenever another creature enters, you may move a +1/+1 counter from this creature onto it.)
{G}: Target creature with a +1/+1 counter on it gains reach until end of turn. (It can block creatures with flying.)

Courage in Crisis

Put a +1/+1 counter on target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Unbounded Potential

Choose one —
• Put a +1/+1 counter on each of up to two target creatures.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Entwine {3}{W} (Choose both if you pay the entwine cost.)

Feat of Resistance

Put a +1/+1 counter on target creature you control. It gains protection from the color of your choice until end of turn. (It can't be blocked, targeted, dealt damage, enchanted, or equipped by anything of that color.)

Cytospawn Shambler

Graft 6 (This creature enters with six +1/+1 counters on it. Whenever another creature enters, you may move a +1/+1 counter from this creature onto it.)
{G}: Target creature with a +1/+1 counter on it gains trample until end of turn.

Chronicler of Heroes

When Chronicler of Heroes enters, draw a card if you control a creature with a +1/+1 counter on it.

Pollenbright Druid

When Pollenbright Druid enters, choose one —
• Put a +1/+1 counter on target creature.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Serrated Arrows

Serrated Arrows enters with three arrowhead counters on it.
At the beginning of your upkeep, if there are no arrowhead counters on Serrated Arrows, sacrifice it.
{T}, Remove an arrowhead counter from Serrated Arrows: Put a -1/-1 counter on target creature.

Satyr Grovedancer

When Satyr Grovedancer enters, put a +1/+1 counter on target creature.

Martyr for the Cause

When Martyr for the Cause dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Iron Apprentice

Iron Apprentice enters with a +1/+1 counter on it.
When Iron Apprentice dies, if it had counters on it, put those counters on target creature you control.

Crowned Ceratok

Trample
Each creature you control with a +1/+1 counter on it has trample.

Maelstrom Colossus

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Backup Agent

When Backup Agent enters, put a +1/+1 counter on target creature.

Hand of Emrakul

You may sacrifice four Eldrazi Spawn rather than pay this spell's mana cost.
Annihilator 1 (Whenever this creature attacks, defending player sacrifices a permanent.)

Star Pupil

Star Pupil enters with a +1/+1 counter on it.
When Star Pupil dies, put its counters on target creature you control.

Grafted Growth

Enchant land
When Grafted Growth enters, put a +1/+1 counter on target creature or Vehicle you control.
Enchanted land has "{T}: Add two mana of any one color."